A Systematic Review of Screen Time and Obesity in Children, Adolescents, and Young Adults: Sex-Specific Pathways and Implications for Public Health Interventions

Introduction: Screen time is associated with multiple adverse health outcomes, including obesity. However, evidence for children and adolescents is limited and inconsistent, and potential sex-specific differences have not been characterized. This systematic review aimed to synthesize evidence on the association between screen time and obesity-related outcomes among children, adolescents, and young adults, with a focus on sex-specific pathways and implications for public health interventions. Methods: This systematic review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines and was based on an a priori protocol. Two reviewers independently selected studies, extracted data, and assessed risk of bias using the Newcastle-Ottawa Scale. Data were synthesized based on the direction of associations and patterns of sex differences. Results: Of the 22 studies included, 18 reported a significant positive association between screen time and obesity-related outcomes. Sex-specific patterns were also observed, with some studies reporting associations only among females (n = 6) or males (n = 4). Among females, observed associations more frequently involved adiposity, metabolically unhealthy obesity, and psychologic factors such as body image concerns and weight dissatisfaction, whereas among males, associations were more often linked to behavioral factors such as increased caloric intake, late-night screen use, and reduced sleep. Conclusion: Our findings indicate that screen time is associated with obesity among children, adolescents, and young adults, with evidence suggesting potential sex differences in the behavioral, physiologic, and psychologic mechanisms. These findings highlight the need for interventions that move beyond simple screen time reduction and consider the mechanisms that may underlie sex-related differences in obesity risk. Potential strategies may include promoting physical activity among girls and addressing problematic screen use, screen-related eating, and sleep disruption among boys, as well as integrating screen-related psychosocial factors into obesity prevention and management. Given the limited number of studies formally assessing sex-screen time interactions, further research is needed to better characterize these observed patterns.